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Part of the book series: Marine Science ((MR,volume 9))

Abstract

The exponential decreases with depth of Be10, Th230 and Pa231 in two manganese nodules from the central North Pacific is interpreted in terms of slow growth of the nodules: at average rates of millimeters per million years. We observe in one specimen (Mn 139): Be10-based rate < Th230-based rate < Pa231-based rate. This suggests that diffusion-mixing may have modified the depth gradients of these nuclides, such that the true rate would be close to or even lower than the observed Be10 rate of 1.3 mm/106yr. Quantitative assessment using a diffusion-decay model indicates that in Mn 139, Th230 and Pa231 could have been subjected to diffusion-like transport with an effective diffusion coefficient of ∿ 1x10−8cm2/yr. After correction for this effect, the Th230 and Pa231 data give a concordant rate of 1.9 mm/106yr, about 2–3 times lower than their uncorrected values. The small and variable amounts of integrated dpm/cm2 of Be10, Th 230ex and Pa 231ex found in nodules are best explained by their incorporating only a fraction of the nuclides supplied due to frequent coverage by sediments. The alternative explanation of young “exposure” ages is refutable on several grounds. Among these, we show that diffusion of nuclides required by the exposure-age concept yields depth profiles that are not of the commonly observed exponential form.

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References

  • Amin, B. S., Lai, D. and Somayajulu, B. L. K. (1975) Chronology of marine sediments using the Be10 method: intercomparison with other methods. Geochim. Cosmochim. Acta 39, 1187–1192.

    Article  Google Scholar 

  • Arrhenius, G. (1967) Deep-sea sedimentation: a critical review of U.S. work. Trans. Am. Geophys. Union, 48, 604–631.

    Google Scholar 

  • Bender, M. L., Ku, T. L. and Broecker, W. S. (1966) Manganese nodules: Their evolution. Science 151, 325–328.

    Article  Google Scholar 

  • Bhat, S. G., Krishnaswami, S., Lai, D., Rama and Somayajulu, B. L. K. (1973) Radiometric and trace elemental studies of ferromanganese nodules. Proc. Symp. Hydrogeochem. Biogeochem., I, 443–462, Clarke, Washington, D.C.

    Google Scholar 

  • Carslaw, H. S. and Jaeger, J. C. (1959) Conduction of Heat in Solids (2nd edition) Oxford Univ. Press.

    Google Scholar 

  • Duursma, E. K., and Hodge, C. (1967) Theoretical, experimental and field studies concerning molecular diffusion of radioisotopes in sediments and suspended solid particles of the sea, Part A: theoretical and mathematical calculation. Netherland Jour. Sea Res. 3, 423–457.

    Google Scholar 

  • Guichard, F., Reyss, J. L. and Yokoyama, Y. (1978) Growth rates of manganese nodules measured with 10Be and 26A1. Nature 272, 155–156.

    Article  Google Scholar 

  • Krishnaswami, S. and Cochran, J. K. (1978) Uranium and thorium series nuclides in oriented ferromanganese nodules: growth rates, turnover times and nuclide behavior. Earth Planet. Sci. Lett. 40, 45–62.

    Article  Google Scholar 

  • Krishnaswami, S., Somayajulu, B. L. K. and Moore, W. S. (1972) Dating of manganese nodules using beryllium-10. In Papers from a Conference on Ferromanganese Deposits on the Ocean Floor (ed. D. R. Horn ) 117–122. NSF, Washington, D.C.

    Google Scholar 

  • Ku, T. L. (1972) Radium in the ocean. In Encyclopedia of Geochemistry and Environmental Sciences (ed. R. W. Fairbridge ), 1008–1014, Van Nostrand Reinhold, N.Y.

    Google Scholar 

  • Ku, T. L. (1977) Rates of accretion. In Marine Manganese Deposits (ed. G. P. Glasby ) 249–267, Elsevier, N.Y.

    Chapter  Google Scholar 

  • Ku, T. L. and Broecker, W. S. (1969) Radiochemical studies on manganese nodules of deep-sea origin. Deep-Sea Res. 16, 625–637.

    Google Scholar 

  • Ku, T. L. and Knauss, K. G. (1978) Radiocative disequilibrium in fissure-filling material and its implication in dating of manganese nodules. Collogue International du C.N.R.S. No. 289 sur la Genèse des Nodules de Manganèse, Gif-sur-Yvette, 25–30 September.

    Google Scholar 

  • Ku, T. L., Knauss, K. G. and Lin, M. C. (1975) An evaluation of dating nodules by the uranium series isotopes. ESS, Trans. Am. Geophys. Un. 56, 999.

    Google Scholar 

  • Lai, D. and Schink, D. R. (1960) Low background thin-wall flow counters for measuring the beta activity of solids. Rev. Sci. Instr. 31, 395–398.

    Article  Google Scholar 

  • Lalou, C. and Brichet, E. (1972) Signification des mesures radio-chimiques dans l’évaluation de la vitesse de croissance des nodules de manganèse. C. R. Acad. Se. Paris. Série D, 275, 815–818.

    Google Scholar 

  • Lalou, C., Ku, T. L., Brichet, E., Poupeau, G. and Romary, P. (1978) TECHNO encrustation I: radiometric studies. Collogue International du C.N.R.S. No. 289 sur Genèse des Nodules de Manganèse, Gif-sur-Yvette, 25–30 September.

    Google Scholar 

  • Li, Y. H. and Gregory, S. (1974) Diffusion of ions in sea water and in deep-sea sediments. Geochim. Cosmochim. Acta 38, 703–714.

    Article  Google Scholar 

  • Wolberg, J. R. (1967) Prediction Analysis. Van Nostrand, Princeton, New Jersey.

    Google Scholar 

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© 1979 Plenum Press, New York

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Ku, T.L., Omura, A., Chen, P.S. (1979). Be10 and U-Series Isotopes in Manganese Nodules from the Central North Pacific. In: Bischoff, J.L., Piper, D.Z. (eds) Marine Geology and Oceanography of the Pacific Manganese Nodule Province. Marine Science, vol 9. Springer, Boston, MA. https://doi.org/10.1007/978-1-4684-3518-4_26

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  • DOI: https://doi.org/10.1007/978-1-4684-3518-4_26

  • Publisher Name: Springer, Boston, MA

  • Print ISBN: 978-1-4684-3520-7

  • Online ISBN: 978-1-4684-3518-4

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